USN-3576-1: libvirt vulnerabilities

Releases

• Ubuntu 17.10
• Ubuntu 16.04 ESM
• Ubuntu 14.04 ESM

Packages

• libvirt - Libvirt virtualization toolkit

Details

Vivian Zhang and Christoph Anton Mitterer discovered that libvirt
incorrectly disabled password authentication when the VNC password was set
to an empty string. A remote attacker could possibly use this issue to
bypass authentication, contrary to expectations. This issue only affected
Ubuntu 14.04 LTS and Ubuntu 16.04 LTS. (CVE-2016-5008)

Daniel P. Berrange discovered that libvirt incorrectly handled validating
SSL/TLS certificates. A remote attacker could possibly use this issue to
obtain sensitive information. This issue only affected Ubuntu 17.10.
(CVE-2017-1000256)

Daniel P. Berrange and Peter Krempa discovered that libvirt incorrectly
handled large QEMU replies. An attacker could possibly use this issue to
cause libvirt to crash, resulting in a denial of service. (CVE-2018-5748)

Pedro Sampaio discovered that libvirt incorrectly handled the libnss_dns.so
module. An attacker in a libvirt_lxc session could possibly use this issue
to execute arbitrary code. This issue only affected Ubuntu 16.04 LTS and
Ubuntu 17.10. (CVE-2018-6764)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 17.10

• libvirt-bin - 3.6.0-1ubuntu6.3
• libvirt0 - 3.6.0-1ubuntu6.3

Ubuntu 16.04

• libvirt-bin - 1.3.1-1ubuntu10.19
• libvirt0 - 1.3.1-1ubuntu10.19

Ubuntu 14.04

• libvirt-bin - 1.2.2-0ubuntu13.1.26
• libvirt0 - 1.2.2-0ubuntu13.1.26

After a standard system update you need to reboot your computer to make
all the necessary changes.

References

• CVE-2016-5008
• CVE-2017-1000256
• CVE-2018-5748
• CVE-2018-6764